February 6, 2008 Construction work on the Beijing National Aquatic Center began in December 2003 in preparation for the 2008 Olympics and four years later, a stunning piece of architecture has been completed. The “Water Cube” is a rectangular-shaped steel building covered by a membrane of brightly lit blue bubbles which is incredible to look at but it is also important on an environmental level. The Water Cube consists of 100,000 sq m of ETFE, (Ethylene Tetrafluoroethylene) a unique transparent plastic which absorbs solar radiation and reduces thermal loss. This is the first time EFTE has been used in China and it is the world’s largest and most complex EFTE building ever constructed.
EFTE is recyclable and light (1% the weight of glass) but it is also strong, capable of bearing up to 400 times its own weight. As it lets in more light and is a better insulator than glass it will reduce energy costs in the Water Cube by 30%. The Water Cube’s structure consists of 3,000 pneumatic cushions ranging from with different sizes from 9sqm to less than 1sqm in size. These "air bubbles" are relatively independent of each other so they can be easily replaced. The LED-lit bubbles allow warm air to enter the building and keep the water temperature at an optimum 28 degrees, but the air can also be stored and used in the Water Cube when required.
The building has outdoor and indoor air recycling systems, solar energy and double-deck ventilation devices. The air-conditioning system uses recycled hot water and the designers engineered the airflow in the Water Cube to ensure that the ventilation in the upper regions of the building was optimized.
To help keep humidity at 50-60%, air ventilation systems at the lower end of the roof and in the façade of the building shell were also installed. Also, the pool’s depth is 13 meters, which helps to reduce the interference of water temperature variation.
The Water Cube spans 80,000-sq-m and was constructed with 6,700 tons of steel, but as EFTE spans greater distances than glass it needed less supportive steel structure beneath it.
Further water-saving and environmental protection measures are featured on the outer surface and façade of the roof which can collect tens of thousands of tons of water annually. During the Olympics, the Water Cube will seat 17,000 fans and 42 gold medals will be up for grabs in swimming, diving, synchronized swimming and water-polo final during the Games.
However, unlike the nearby National Stadium or “Bird’s Nest” which people fear may lay dormant after the Games, the Water Cube will be converted into a multi-functional facility for sports, culture and recreation, including a café and waterslide. As EFTE has an expected life span of up to 50 years the Water Cube is guaranteed to live on far beyond 2008.
The USD$100 million "Water Cube" project was born out of an international competition won by a design consortium consisting of China State Construction Engineering Corporation, China State Construction International (Shenzhen) Design Co., Ltd, PTW Architects (Australia) and Ove Arup (Australia).
See the Beijing 2008 site to learn more.